#include<bits/stdc++.h>
using namespace std;
using ll = long long;
#define itn int
#define rep2(i,a,n) for(int i = (a);i < (n);i++)
#define rep(i,n) rep2(i,0,n)
using P = pair<int,int>;

int main(void){
    int n;
    cin >> n;
    
    ll j = 1;
    for(int i = 0;;i++){
        if(j >= n){
            cout << i << endl;
            break;
        } else j *= 2;
    }
    
}